In recent years, mobile telecommunications carriers have experienced a dramatic increase in traffic, particularly data traffic, on their networks, and this trend will likely continue. This increase in traffic has been caused in part by the increased adoption of smartphones and other devices that rely on mobile telecommunications networks, the migration of many customers from utilizing landline telecommunication services to utilizing mobile telecommunication services for their communications needs, and the use of multimedia such as streaming video, high-definition video games, and photo-intensive social media. To meet the demands of higher traffic and to improve the end user experience, mobile telecommunications carriers are examining mechanisms by which to improve network efficiency, network capacity, and the end user experience, while keeping operational costs at a level conducive to maintaining competitive rates for the services they provide.
Software-defined networking (“SDN”) is an architectural framework for creating intelligent networks that are programmable, application aware, and more open. SDN provides an agile and cost-effective communications platform for handling the dramatic increase in data traffic on carrier networks by providing a high degree of scalability, security, and flexibility. SDN provides several benefits. SDNs can allow for the creation of multiple, virtual network control planes on common hardware. SDN can help extend service virtualization and software control into many existing network elements. SDN enables applications to request and manipulate services provided by the network and allow the network to expose network states back to the applications. SDN exposes network capabilities through application programming interfaces (“APIs”), making the control of network equipment remotely accessible and modifiable via third-party software clients, using open protocols such as OpenFlow, available from Open Network Forum (“ONF”). Third Generation Partnership Project (“3GPP”) and other standards bodies and industry forums are currently working to standardize SDN for use in multiple aspects of future mobile telecommunications networks under fifth generation (“5G”) standards. In part, the radio access network (“RAN”) will be implemented using SDN concepts.
Future RANs will provide a greater level of densification with the deployment of small cells that utilize, for example, millimeter (“mm”) wave spectrum to offer higher data rates and user throughput to meet the bandwidth demand expected for 5G services. In the mm-wave range, the cell size is much smaller and the number of these smaller cells needed will be much greater. A challenge of deploying such large numbers of small cells lies in operations, and in particular, how to deploy large numbers of small cells with automation instead of operations support system (“OSS”) manual configuration. One important aspect of such operation is network discovery—that is, how added, deleted, or changed small cells can be automatically discovered to enable greater collaboration among cells. Existing small cells and macro cells can discover neighboring small cells by OSS manual configuration and/or by using RF signal detection. This method of discovery allows a cell to discover its immediate neighbor(s). Greater cross layer optimization can be achieved because SDN has a global abstraction of both wire and wireless networks.
While the industry is moving towards leveraging SDN for RAN due to the flexible/programmable common control and higher degree of collaboration among small cells, macro cells, and even among different radio technologies for the higher layer functions such as load balancing, mobility, interference mitigation, and the like, the existing localized network listening discovery or OSS manual configuration will no longer function. This is because many of the small cells are not immediately connected to the SDN controller and some are likely many hops away from the SDN controller.